1. The Field of the Invention
The present invention generally relates to devices and methods for gaining additional height to perform various activities. More specifically, the present invention relates to a vehicle mountable lifting apparatus that is adapted for elevating and lowering objects and/or individuals to various desired heights.
2. The Prior State of the Art
Through the ages man has desired to perform activities at different heights, such as harvesting food, maintaining building structures, installing equipment, and the like. With advances in technology, numerous devices have been developed to allow an individual to perform activities at various heights that were previously performed with the use of a ladder or other similar height gaining apparatus. Though many different adjustable platforms or height gaining or lifting apparatus have been developed, these devices have various drawbacks that make them difficult to use or difficult to transport, or have other drawbacks that reduce their effectiveness.
Traditionally, in a working environment, an individual may gain additional height through the use of scaffolding. Scaffolding allows an individual to have a steady platform from which to perform various activities, such as painting, construction, and the like. Generally, scaffolding consists of a number of scaffolding sections, such as supports and cross-members that are connected together to form a scaffolding framework. Upon this framework a number of planks or other platform-type structures are placed that provide an area from which an individual may work or store materials and equipment. Greater height may be achieved with scaffolding by attaching additional scaffolding frameworks and platforms. Though scaffolding is useful for achieving a great height, it is necessary to transport a large number of supports, cross-members, and platforms resulting in high installation costs and extended installation time.
One apparatus that overcomes the difficulties associated with transporting scaffolding is the scissor lift-type platform. Traditional scissor lifts include a number of pivotal lift elements that are each pivotally joined to subsequent lift elements, the platform, and/or the base of the scissor lift. Disposed between the platform and the base member, while being attached to a number of lift elements, is a hydraulic ram. The hydraulic ram raises the platform by moving the individually joined lift elements to form the typical cross-type configuration. Conventionally, the base of the scissor lift includes a driving motor that allows the scissor lift to move from location to location. Alternatively, the scissor-lift may be located on a vehicle, such as a pickup truck, which substitutes for the motorized portion of the base.
Unfortunately, traditional scissor lifts are expensive and costly to use. Furthermore, each scissor lift is somewhat function specific, in that different scissor lifts are required for rough or generally level terrain. Though a few scissor lifts are truck mounted, the majority of the available scissor lifts must be transported to the particular worksite, whether on the back of a vehicle, such as a pickup truck, and then removed, or towed behind a truck. Both truck mounted and mobile scissor lifts are, however, capable of carrying only small loads. Additionally, scissor lifts generally must be lowered to allow an individual to enter or exit the platform making the devices inconvenient to use. Furthermore, typical vehicle mounted scissor lifts are difficult to install and remove from the vehicle as is required for maintenance and the like adding to the costs and inconveniences of use.
Another type of device that allows an individual to gain greater height is the boom-type adjustable platform. Boom-type adjustable platforms have a basket or other platform attached to one end of a sliding boom. The opposite end, distal to the platform or basket, is connected to a base that is capable of moving the sliding boom in various directions, such as rotating the sliding boom about the axis of the base or sliding the boom inwardly or outwardly. This type of lift, however, is only capable of carrying a limited load determined by the load or weight of the base. Too great a load carried on the platform at too acute an angular orientation of the boom relative to the base results in tipping of the adjustable platform. As with the scissor lift apparatus, the boom lift suffers from similar defects in that it must be transported with the aid of another vehicle, such as being pulled behind a truck. Alternatively, the boom-type lift may be driven to a particular location; however, this driving requires a significant amount of time, due to the inherently low traveling speeds of the boom-type adjustable platform.
Various other types of apparatus that are capable of raising a single individual to a specific height are known. Many of these devices, however, are incapable of carrying a sufficient load, such as materials, equipment or the like, that are required by an individual working at a great height. Additionally, these devices are difficult to transport to the location of use and to install on the transporting vehicle. For example, previous vehicle mounted apparatus for gaining additional height require the use of cranes, forklifts, or other lifting devices to securely position the lifting apparatus on the vehicle. Furthermore, many previous vehicle mountable lifting apparatus require difficult or permanent connection to the vehicle, thus requiring significant installation time and expense.
It would be an advance to provide an adjustable lifting apparatus that transports easily and carries large loads. It would be a further advance to have an adjustable lifting apparatus that is capable of being vehicle mounted to thereby allow easy transportation and use of the platform. Still it would be another benefit or advance to have a lifting apparatus that allows an individual to access a platform whether or not the platform is an extended or retracted orientation.
It is an object of the present invention to provide a vehicle mountable lifting apparatus that may elevate objects and/or persons to varying heights.
Another object of the present invention is to provide a vehicle mountable lifting apparatus that can carry various loads having differing lengths and configurations.
Another object of the present invention is to provide a vehicle mountable lifting apparatus that is inexpensive to manufacture while including a large working area.
Yet another object of the invention of the present invention is to provide a lifting apparatus that includes safety mechanisms to ensure the safety of the operators.
Another object of the present invention is to provide a lifting apparatus that can easily be transferred from one vehicle to another without the use of cranes, forklifts, or other similar devices.
It is another object of the present invention to provide a lifting apparatus that uses the characteristics of the vehicle upon which it is mounted to provide stability and support to the lifting apparatus.
A further objective of the present invention is to provide a method for removing and mounting a lifting apparatus to a vehicle.
Additional objects and advantages of the present invention will be set forth in the description that follows in conjunction with the accompanying figures, and in parts will be obvious from the description, or may be learned by the practice of the invention. The objects and advantages of the invention may be realized and obtained by means of the instruments and combinations particularly pointed out in the appended claims.
To achieve the foregoing objects, and in accordance with the invention as embodied and broadly described herein, a lifting apparatus for mounting to a vehicle is disclosed. The lifting apparatus includes a base assembly that is adapted to cooperate with the vehicle. The base assembly includes a base having a plurality of columns extending therefrom. Coupled to the base is a connecting mechanism, such as a bulldog/goose neck hitch, that allows secure attachment of the base assembly to the vehicle. The lifting apparatus further includes a platform assembly that has a platform and a plurality of outer column receivers extending from the platform. The outer column receivers cooperatively engage with the columns of the base assembly to allow sliding engagement of the platform assembly and the base assembly. In one embodiment, the platform assembly includes a railing assembly that surrounds the peripheral edge of the platform.
Cooperating with the platform assembly and the base assembly is a driving mechanism that is adapted to reversibly elevate the platform assembly relative to the base assembly. The driving mechanism includes a motor assembly that drives a gear assembly. The gear assembly has a plurality of sprockets that cooperate with a lifting chain that is attached to both the base assembly and the platform assembly. As such, as the motor assembly drives the gear assembly, the plurality of sprockets engage with the lifting chain to move the platform assembly or the base assembly relative to each other.
In one embodiment of the present invention, the lifting apparatus further includes a safety mechanism that is adapted for controlling the descent of the platform assembly relative to the base assembly in the event of a malfunction of the lifting apparatus.
The embodiments of the present invention may utilize a method to install and remove the lifting apparatus without the need for traditional installation equipment, such as forklifts, cranes, and the like. The method of installing and removing or loading and unloading the lifting apparatus includes a number of loading/unloading posts, that have sliding mechanisms that slide along the longitudinal length of the posts as the platform is raised and lowered. The combination of the posts and sliding mechanisms retains the platform at the required height for installation and removal of the platform from a vehicle.